The Shambulance: Deer Antlers Are Not Unicorn Horns

The Shambulance is an occasional series in which I try to find the truth about bogus or overhyped health products. The chief navigational officer of the Shambulance today is Steven Swoap.

This Superbowl season saw a star linebacker forcefully denying that he'd ever sprayed juice made from ground-up deer antlers into his mouth. The player was Ray Lewis, and using deer antler spray would have seemingly violated the National Football League's ban on performance-enhancing drugs. Like the horn of a unicorn, this product is alleged to heal and strengthen its users. Also like the unicorn horn, it's probably not something the NFL needs to worry about.

Bottles of deer antler spray—also called deer antler velvet or IGF-1 spray—are legal and easy to purchase for $20 to $50. Though no one's checking what's actually inside the bottles, makers claim their products come from antlers that are harmlessly sawed off of male deer each spring, or from the soft skin covering these new antlers. A few times a day, you spritz the solution into your mouth and swallow it.

The suggestion is that deer antler spray will make your own muscles or bones regrow as rapidly as a deer's antlers. Some products make other claims that are variously expansive, including weight loss, better endurance, a boosted immune system, and higher sex drive. Fueling all these promises is a hormone called IGF-1 (short for insulin-like growth factor). Like medieval "unicorn horns" that were really the tusks of narwhals, IGF-1 is less glamorous in reality than in legend.

It's true that deer antlers "grow like crazy," says Steven Swoap, a physiologist at Williams College. "There are not many examples where a tissue grows faster than an antler. Except for maybe some pumpkins."

We humans are naturally curious about tapping into that growing power. And IGF-1 is certainly involved in growth. In humans as well as deer, it's mostly manufactured by the liver. We make more of it during growth spurts, Swoap says. Producing too much IGF-1 is linked to certain cancers—growth that can't be stopped.

"Does IGF-1 cause antler growth? It is possible," Swoap says. "A more likely candidate is testosterone." Female deer, which also make IGF-1, don't grow antlers; male deer have extra testosterone in their bodies during the antler-growing season. "There are likely many factors involved," Swoap says.

Whatever ingredient gives deer antlers their seemingly magical growing power, we aren't likely to capture much of it by grinding up the antlers themselves. "The antler is not a hormone producing factory," Swoap says. Antler growth is triggered by hormones sent from elsewhere in the body, such as the liver, thyroid, or testes. ("You would be much better off making a spray out of the testes of deer," Swoap suggests. "Or you could perhaps get the IGF-1 from the liver, where it is made, and have a liver milkshake with your deer nut spray.")

Even if a useful quantity of IGF-1 made it out of the antlers and into the spray, the molecule would have a hard time completing its journey into the hopeful athlete's body. Swoap says IGF-1 is a hefty protein that's unlikely to slip into your bloodstream through the soft tissues under your tongue. And once swallowed, it would break down in your digestive tract.

Swoap compares IGF-1 to another famous protein hormone: insulin. "For years, we had to inject it, and it is only recent technological advances that allowed us to deliver it subcutaneously," he says. "To say that the technology is replicated in a bottled spray is ridiculous."

Mitch Ross, the owner of the company that claimed Ray Lewis used its deer spray to recover from an injury, calls his products "technologies that are light years ahead of what people can understand." In other words, even if we can't explain the science, we should accept that deer antler extract helps people.

Except that it doesn't.

Researchers have given oral deer antler supplements to various groups of people, compared them with placebos, and looked for any effect. Men who took deer antler supplements during a strength training program showed no change in hormone levels (including IGF-1) and no difference in aerobic endurance. Rowers also showed no change in hormone levels and no difference in strength or endurance. (As for those other claims, a study in middle-aged men found no increase in sexual function.) A review paper last year concluded there is no convincing evidence that deer antler extract is useful to athletes.

It seems we haven't yet lopped anything special off the heads of those deer. Ray Lewis and (because even athletes who compete at a walk apparently want performance boosters) golfer Vijay Singh are busy defending their reputations against deer antler spray. Yet the product wouldn't have given them any extra powers except a placebo spritz of confidence. Professional sports organizations have plenty of real beasts to chase down in the world of banned substances, but this one is only a mythical creature.


Image: skipnclick (Flickr)